Propelling mechanism for bicycles.



No. 65|,244, Patented June 5, I900.

w. H. FORBES. PROPELLING MECHANISM FOR BIGYCLES.

(Application filed Sept. 9, 1899.)

(No Model.)

"if W 2 NlTED STATES- WILSON H. FORBES, OF BEAVER FALLS, PENNSYLVANIA.

PROPELLING MECHANISM FOR BICYCLES.

SPECIFICATION forming part of Letters Patent No. 651,244, dated June 5,1900.

Application filed bfeptember 9, 1899. Serial No. 729N386. (No model.)

To all whom zit-may concern:

Be it known that 1, WILSON H. FORBES, a citizen of the UnitedStates,residin g at Beaver Falls, in the county of Beaver and State ofPennsylvania, have invented new and useful Improvements in PropellingMechanism for Bicycles, of which the following is a specification.

This invention relates to propelling mechanism for bicycles, and has forits object to provide improved driving mechanism by means of which theweight of the rider may be utilized and combined with the propulsiveforce of the legs to drive the bicycle and in which the propulsive forceof the legs may alone be employed when desired.

It also has for its object to provide simple, efficient, and inexpensivemechanism of the character referred to which may be readily applied tobicycles of the ordinary and usual type now in general use.

To these ends my invention consists in the features and in the'construction, combina-v tion, and arrangement of parts hereinafterdescribed,and particularly pointed out in the claims following thedescription, reference bein g had to the accompanying drawings, forminga part of this specification, wherein Figure l is a view in sideelevation of a bicycle provided with my improved propelling mechanism.Fig. 2 is a transverse Vertical sectional view of the propellingmechanism. Fig. 3 is a detail sectional View of a part of the seatpropelling mechanism, and Fig. 4 is a similar view of the footpropelling mechanism.

Referring to the drawings, the numeral 1 indicates the frame ofanordinary and wellknown type of bicycle, and 2 and 3 the driving andsteering wheels thereof. The seatpost tube 4 is hollow and extends fromthe axle-sleeve 5 to the upper part of the frame, as usual. Theseat-post 6 is loosely arranged in the seat-post tube at, so as to befreely movable vertically therein, and carries at its upper end a seat7' of ordinary or any preferred construction. Fixed in the lower part ofthe seat-post tube 4 is a plug 8, on which rests one end of a coiledspring 9, disposed in said tube, the other end of the spring bearingagainst the lower end of the seat-post 6. The spring 9 operates tonormally hold the seat PATENT FFICE.

raised, but should yield under the weight of the rider to permit theseat to descend. Two rods or bars 10 are attached at their upper ends tothe opposite sides of the head 11 of the seat-post and at their lowerends are disposed and vertically movable in guide-sleeves 12. Thesleeves 12 are preferably square in cross-section to conform to thecorresponding shape of the bars 10, whereby the latter are preventedfrom turning, and at their upper ends are fixed in the opposite ends ofa rigid arm 13, which intermediate its ends is formed with a collar 14,that is firmly fixed on the seatpost tube 4. The sleeves 12, near theirlower ends, are formed with rearwardly-projecting lugs 15, which arefitted over the ends of the driving-axle 16 and operate to brace andhold said sleeves perfectly rigid.

Loosely arranged on the axle, near its opposite ends, are twogear-wheels 17, provided on their inner faces with pawls 18, that engageratchet-pinions 19, fixed on the axle, the arrangement being such thatwhen the gearwheels are turned in one direction the pawls engage theratchet-pinions and turn the axle; but when the gear-wheels are turnedin the opposite direction the pawls ride idly over. the ratchet-pinionswithout communicating movement to the axle. The lower portions of thebars 10 are toothed, as at 20, and the guide-sleeves 12 are each slottedon the rear side, as at 21. The gear-wheels 17 project through theslotted portions of the guidesleeves and engage the toothed edges of thebars'lO. Hence reciprocating movement com municated to the rack-barswill be transmitted to the gear-wheels 17 and the driving-axle 16. Thedriving-axle 16 is connected to the axle of the rear wheel bychain-and-sprocket gearing in the usual manner.

Fixed in the outer ends of the arm 13 are two depending guide-sleeves21, similar "in all respects to the guide-sleeves 12, before described,and disposed in said sleeves and vertically movable therein are two bars22, provided at their upper ends with heads or shoulders 23. Arrangedupon the upper portions j of the bars 22 are coiled springs 24, each ofwhich rests at its lower end on the upper end of the sleeve 21 and atits upper end bears against the shoulder 23. The lower ends of the bars22 project through the sleeves 21,

and each is provided with a stirrup or pedal 24, adapted to be engagedby the feet of the rider. The bars 22 are also provided with rack-teeth25, which engage gear-wheels 26, provided with pawls 27, engagingratchetpinions 28, mounted on the driving-axle, precisely in the mannerbefore described.

The operation of my improved driving mechanism is as follows: The riderseats him self in the seat with his feet upon the pedals 24. The weightof the rider causes the seat to descend, thus forcing down the rack-bars10. The downward movement of the rackbars 10 rotates the gear-wheels 17,which in turn rot-ate the ratehet-pinions 19 and turn the driving-axle,and the latter, through the medium of the chain and sprocket,- turn thedriving-wheel 2 to propel the bicycle forward. In the down ward movementof the saddle the riders legs are flexed, and as he straightens out hislegs to raise himself the rack-bars 22 are thrust downward, and thismovement of said rack-bars is transmitted to the drivingwheel in thesame manner as that just above described. When the rider raises himself,the saddle is raised by the spring 9, thus returning the rack-bars 10 totheir former position, the gear-wheels turning idly about theratchet-pinions, and the rack-bars 22 are in like manner raised by thesprings 24 when the saddle again descends. By raising and loweringhimself in the manner described the rider alternately forces downwardthe rackbars 10 and 22, thus communicating a continuous rotary motion tothe driving-axle. At times when but little force is required to propelthe bicycle the rider may remain seated stationary in the saddle andraise and depress his feet alternately, thus alternately depressing therack-bars 22. The rack-bars 10 at such times remain stationary. Incoasting both sets of rack-bars remain stationar the pawls of thegear-wheels riding idly over the ratchet-pinions,whereby the movement ofthe driving-axle does not affect the driving mechanism.

At times it is desirable to hold the seat stationary in its loweredposition, and for this purpose I have provided means constructed asfollows: Attached to the rack-bars 10 is a metallic strap 29, and fixedon the seat-post tube 4 is a collar 30, provided with two lugs 31,between which is pivoted a latch 32, provided with a hooked upper end33, adapted to engage the strap 29 and hold the seat-post clown. Thelatch 32 is formed upon its inner side opposite its pivotal point with aprojection 34, and fixed beneath the latch and between the lugs 31 is afiat spring 35, which is bent outward between its ends into Vshape, asat 36. \Vhen the latch is turned into one or the other of its positions,the V-shaped portion of the spring will engage one side of theprojection on the latch, and thus hold the latch in either its locked orunlocked position. The latch is especially useful in holding the seat inits lowered position while the rider mounts or dismounts and is easilyreached by the rider while in the seat to either lock or unlock thelatch.

By means of my improved propelling mechanism the rider may utilize hisentire weight and apply it to the propulsion of the bicycle in additionto the power of his legs. Constructed as shown itis not necessary thatthe bicycle be especiallyconstructed for the driving mechanism, as thelatter may be readily applied to any of the well-known types of hicyclesnow in general use. It will be obvious that a single rack-bar 10 and itscorre* sponding parts may be employed; but I prefer to employ the doublearrangement shown, as the power is more equally applied to thedriving-axle.

Having described my invention, what I claim is- 1. In a bicycle, thecombination with a vertically-movable seat-post and means fortransmitting the movement thereof to the drivingaxle, of a latch pivotedintermediate its ends to the seat-post tube and arranged to engage anabutment movable with the seat-post to hold the latter in its loweredposition, a projection formed 011 the inner side of said latch oppositeits pivotal point, and a V-shaped spring attached to the seat-post tubeopposite said projection for alternately engaging the latter to hold thelatch in either of its adjusted positions, substantially as describedand for the purpose specified.

2. In a bicycle, the combination with a transverse arm fixed on theseat-post tube, of two guide-sleeves fixed at their upper ends to theopposite ends of said arm, rack-bars movably arranged in saidguide-sleeves and provided at their lower ends with pedals, coiledsprings arranged on the upper portions of the rack-bars and restingattheir lower ends on the said arm and bearing at their upper ends againstshoulders on the upper ends of the rack-bars, gear-wheels looselymounted on the driving-axle and engaging said rackbars, pawls carried bythe gear-wheels and ratchet-pinions fixed on the driving-axle andengaged by the said pawls, substantially as described.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

WILSON H. FORBES.

Witnesses:

JAMES L. NORRIS, F. B. KEEFER.

